Well at least you have it figured out.
Personally, if it was mine, assuming you can find a compressor, I would blow it out, flush as much as you can, replace the drier, and as someone said above, use ester oil. If everything is stock, if possible weigh the charge in.... I think its recommended to use 18%? less with 134a. but check those numbers.
Good luck and look forward to hearing if you get it fixed.
